Plot a changing angle over time
20 views (last 30 days)
Show older comments
Need help regarding the changing angle between 2 vectors of a moving object over time. The 2 vectors are namely the direction vector and the vector referencing to the origin. I am stuck here as i dont know how to proceed to plot the cos_theta over time. Also, i keep getting the dimension mismatch for my cos_theta. Kindly appreciate any help thanks!!
x_i=input('Enter the initial x location of the object: ');
y_i=input('Enter the initial y location of the object: ');
z_i=input('Enter the initial z location of the object: ');
x_f=input('Enter the final x location of the object: ');
y_f=input('Enter the final y location of the object: ');
z_f=input('Enter the final z location of the object: ');
Vel=input('Enter velocity of moving object: ');
N=input('points: ');
initial=[x_i;y_i;z_i];
final=[x_f;y_f;z_f];
direction=final-initial; %Direction vector
coord=[linspace(x_i,x_f,N);linspace(y_i,y_f,N);linspace(z_i,z_f,N)];
dist=sqrt((x_f-x_i).^2+(y_f-y_i).^2+(z_f-z_i).^2); %Distance between final and initial pos
Total_time=dist./Vel; %Total time required to travel
%STUCK FROM HERE ONWARDS
n=linspace(1,N,N);
t=linspace(0,Total_time,N);
cos_theta = dot(direction,coord(:,n))/(norm(direction)*norm(coord(:,n)));
plot(t, cos_theta);
2 Comments
Accepted Answer
David Hill
on 8 Sep 2019
function angleOtime(initial,final,vel,n)
direction=final-initial;
dist=norm(direction);
velocity=(direction/dist).*vel;
t=linspace(0,dist/vel,n);
cos_theta = arrayfun(@(x)dot(direction,x*velocity+initial)/(norm(direction)*norm(x*velocity+initial)),t);
plot(t, cos_theta);
end
If I understood you correctly, the above function should work for you. Just input the initial point [xi,yi,zi], final point [xf,yf,zf], vel, and number of interval desired.
More Answers (0)
See Also
Categories
Find more on Specifying Target for Graphics Output in Help Center and File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!